Pumps and pumping systems exist for the delivery of various fluids. A variety of pumps are used in a number of various different configurations and uses. Pumps are used for infusion of drugs or delivery of drugs into mammals, the sterility of the drugs is very important. In addition, contamination of the drug or delivery fluid from the pump system should be reduced or eliminated. Additionally, it remains an important aspect to minimize contact between the drug to be delivered and the internal components of the pump being used to deliver the drug. Filling or preparing the drug or fluid for delivery should not be time consuming. These and other difficulties are encountered using conventional filling and pumping systems.
Related U.S. application Ser. No. 11/112,867 filed Apr. 21, 2005 titled, “Electrokinetic Delivery Systems, Devices and Methods,” discloses a technique for filling a pump with fluid for delivery. This technique involves operating the pump system in reverse to draw the delivery fluid into the pump. Then, after filling the pump with the delivery fluid, the pump direction is reversed and the delivery fluid is delivered from the pump. Reversing pump direction may be a good solution for small amounts of fluid or for pump configurations that have a very high linear flow rate. However, the time requirements for loading large volumes of delivery fluid using this technique may be prohibitive for time conscious applications and problematic for later pump operation.
What are needed are improved techniques for providing the delivery fluid into the pumping system. The pump filling procedures should be simple and require small amounts of time.